Interpretive Summary: Species of the genus Sarcocystis are single celled parasites. Sarcocystis neurona, is a major cause of neurological disease in horses and many other species of animals. It is transmitted via the fecal oral route from opossums, the only known definitive host, to an unusually wide array of intermediate hosts including raccoons, armadillos, cats, marine mammals, skunks and brown-headed cowbirds. In the present paper authors characterize two new species of Sarcocystis from wolverines, first time from this host. The results will be of interest to biologists, parasitologists, and veterinarians.

Technical Abstract:
Infection with Sarcocystis species is common in many species of animals, but has not yet been reported in wolverines (Gulo gulo). Histological sections of tongues of 41 wolverines from Kitikmeot Region, Nunavut, Canada were examined for sarcocysts. Sarcocysts were found in 33 (80.4%) wolverines. Two structurally distinct types of sarcocysts were found. Type A sarcocysts were thin (<1 µm thick) walled, the parasitophorous vacuolar membrane (Pvm) had minute undulations but lacked villar protrusions, and was not invaginated into the granular layer. The bradyzoites were slender, about 5 x 1 µm in size. Structurally, these sarcocysts were distinct from known species of Sarcocystis and possessed a novel ITS-1 sequence sharing only 78% sequence similarity with Sarcocystis canis. A new species name Sarcocystis kalvikus is proposed for Type A sarcocysts. In contrast, type B sarcocysts had relatively thicker (about 2 µm thick) cyst walls and larger bradyzoites each about 10 µm x 2-3 µm. The Pvm on the sarcocyst wall had villar protrusions that were flattened and either mushroom-like or sloping, based on the plane of section. Molecular analysis identified unique ITS-1 sequence, and based on histology, TEM and genetic data, the new name Sarcocystis kitimeotensis is proposed. Sarcocystis kalvikus was found in 14 (34.1%), S. kitikmeotensis in 7 (17%), and both species in 12 (29.2%) of 41 wolverines.